Software and hardware will be developed to visuaalize the estimated extent and time course of activity within the brain from an array of EEG electrodes placed on the scalp. This requires the development, implementation, and validation of signal processing algorithms to identify appropriate signal components and estimate the source locations and time course. Preliminary results suggest the feasibility of the approach, which uses novel linear estimation techniques, not currently available for the analysis of electrical recordings. Methods will be verified using phantoms (phase I) and physiological data (phase II). Potential applications of these methods include both research and eventual clinical uses, such as the localization and lateralization of language function, monitoring of stroke and psychiatric disorders, and the estimation of cortical activity during sensory evoked responses and cognitive activity.